The TWAIN Working Group maintains open source sample code (BSD license) for both TWAIN applications and TWAIN drivers (data sources) at the following location:
http://sourceforge.net/projects/twain-samples/

I downloaded twainds.source.2.1.3.zip, unzipped, opened Twain_DS_sample01visual_studioTWAINDS_VS2008.sln and it was converted to Visual Studio 2010(My Visual Studio version is 2010)
Compiled it but compile error occurs like attached screen capture.
How could I fix this error?

In my case, The Source is the object of development among the Application, The Source Manager and The Source, is it right?
In the 2-4 State Transition Diagram of the TWAIN Specification 2.2, there are 7 steps like following.
1 : Pre-Session
2 : Source Manager Loaded
3 : Source Manager Opened
4 : Source Open
5 : Transfer Ready
6 : Source Enabled
7 : Source Open

I need sample source code regarding 4~7.
Can you let me know the location I can download it?